MORRISVILLE, N.C. – Stock in biopharmaceutical firm Trimeris plunged 29.3 percent in trading on Wall Street today, the sell-off triggered by management changes and the end of a partnership with drug giant Roche that were announced on Thursday.

Several analysts cut their rating for Trimeris (NASDAQ: TRMS), helping ignite a frenzy in trading. Nearly 4.4 million shares were traded. Typically trading volume is 211,000 shares a day.

Trimeris sells in conjunction with Roche an AIDS drug called Fuzeon, and Trimeris did for the first time report a profitable year on Thursday in its annual earnings report. However, news that co-founder and chief executive officer Dani Bolognesi would retire effective Friday overshadowed the positive earning news. Robert Bonczek, the chief financial officer, also is retiring.

Bolognesi, a former Duke professor, is a pioneer in HIV research. He helped launch Trimeris in 1993.

Trimeris also disclosed Thursday that a development relationship with Roche for a future AIDS drug was terminated with Trimeris regaining control of the compound. However, its partnership with Roche for Fuzeon sales, marketing and production remains in place.

The news led some analysts to change their view of the stock.

Analyst firm Stifel Nicolaus & Company reiterated its "hold" rating on the stock and raised its earnings per share forecast for 2007 to 59 cents from 8 cents. However, other firms lost confidence.

First Albany cut Trimeris to “neutral” from the “buy” rating it had set in November.

At ThinkEquity Partners, Trimeris was cut to “sell” from “accumulate.”

At Merrill Lynch, analyst Steven Harr described Trimeris as appearing “to be a ship without a rudder, lacking both permanent management and a short or long-term strategy.”